The invention pertains to a body-side mounting for a suspension strut or spring shock absorber of a motor vehicle, with a rubber mount effective between the body and suspension strut, predominantly loaded in shear, which is placed between a mount receptacle formed into the body or parts thereof and a spacer joined to the suspension strut, with the mount receptacle and spacer being adjusted to the dimensions of the rubber mount and receiving the latter in the inward spring deflection direction and radially thereto.
A body-side mounting of this kind, in which, however, the mount located between the mount receptacle and spacer is configured as a rubber-metal mount, is known, for example, from DE-PS No. 30 41 985. The rubber-metal mount consists of a cylindrical inner sheet-metal casing, joined with the shock absorber piston rod or the housing of the suspension strut, possibly with a roller bearing or plain bearing interposed, a rotationally symmetrical and conically shaped outer sheet-metal casing joined to the body and an annular rubber element adhesively vulcanized between the inner and outer sheet-metal casings, predominantly loaded in shear. The outer sheet-metal casing is inserted from below into the mount receptacle matched to its dimensions and is received therein in a form-fitting manner in the spring deflection direction and perpendicularly thereto, while the outer sheet-metal casing is held in the mount receptacle in the outward spring deflection by frictional engagement alone.
The known mounting has proved entirely successful in practice, but has the critical disadvantage that the rubber-metal mount can only be produced with a large outlay in terms of manufacturing and cost. For example, the mount requires both an inner sheet-metal casing and an outer sheet-metal casing, which are to be adjusted to the mounting elements on the body side and on the suspension strut or spring shock absorber side; moreover, the rubber element shaped to correspond to the contour of the inner and outer sheet-metal casings must be adhesively vulcanized to these parts.
DE-GM No. 1,960,990 discloses a body-side mounting for a suspension strut or spring damper of a motor vehicle, in which a simple annular rubber mount is received between a rotationally symmetrical body-side mount receptacle and a spacer, also shaped with rotational symmetry, joined to the suspension strut. Although the rubber mount represents a considerable simplification in design over a rubber-metal mount and thus can also be produced more economically, it displays decisive disadvantages under a load in the radial direction, for example, when the steering is at full lock. For example, a radial load on the rubber mount causes the rubber to shift from the loaded side to the unloaded side, which is accompanied by creep behavior and a degressive spring stiffness, resulting in unstable steering response. Besides this, the creep behavior of the rubber ring results in increased wear on the rubber mount.
To improve the damping properties of the body-side mounting of the suspension strut or spring shock absorber, DE-GM No. 1,960,990 furthermore recommends that the rubber mount be provided, at its contact surface with the body-side mount receptacle, with indentations that gradually come into contact with the mount support as the compression load increases. As a result, the spring constant decreases as the compression load increases, and the transition from a low spring constant with shear load to a higher spring constant with compression load is smoothed out, except, however, that creep behavior by the rubber mount under shear load cannot be prevented.
The object of the present invention is to create a body-side mounting of the aforesaid type in which the rubber mount itself, when radial forces are introduced as a result of full steering lock, guarantees a largely constant spring rate and therefore stable steering response.
The object is achieved by the fact that teeth are provided on the inside of the mount receptacle and on the outside of the spacer, which engage in teeth in the rubber mount.
The configuration of the body-side mounting according to the invention in the region of the mount receptacle, the rubber mount and the spacer causes creep behavior of the rubber to be prevented under all driving conditions of the motor vehicle. For example, when there is a radial load on the rubber mount, because of its form-fitting joints with the mount receptacle and the spacer, the rubber does not shift from the loaded to the unloaded side of the rubber mount; it is thus held in position and guarantees stable steering response along with progressive spring stiffness.
The configuration of the body-side mounting according to the invention in the region of the aforesaid components makes it possible, with reference to the rubber mount, to eliminate the rubber-metal joint, so that the mount can be produced much more economically and there is also a reduction in scrap as compared to a rubber-metal joint. Moreover, the simple configuration of the rubber mount and of the mount receptacle and spacer allows a reduction in costs for production of the parts and thus a decrease in product cost.
Especially good mounting properties, particularly with regard to steering response, can be achieved with the body-side mounting when the motor vehicle has a top-mounted steering system and therefore, because of the overhead attachment point, when greater radial forces can be introduced into the rubber mount. Even in the case of a bottom-mounted mounting, with consequently lower radial forces, the body-side mounting according to the invention is regarded as conditionally necessary.
One especially simple design configuration of the body-side mounting provides for the mount receptacle and spacer to be configured as stamped sheet-metal parts and for the teeth of these parts to be present as depressions and projections in the particular stamped sheet-metal part. They should advantageously extend regularly over the inner circumference of the mount receptacle and the outer circumference of the spacer, respectively, and preferably be located in the regions with which the rubber mount comes into contact when radial forces are introduced.
Additional features of the invention are presented in the description of the figures; note that all individual features and all combinations of individual features are essential to the invention.